Abstract:

Abstract:Objective To investigate the influence of atorvastatin in methylation and expression level of Bcl-2 in human umbilical endothelial cells(HUVECs) treated with homocysteine(Hcy) and to expound potential mechanism of atorvastatin resisting arteriosclerosis.Methods After HUVECs were treated with 0,2,4,8,16,and 32 mmol/L  Hcy for 48　h,MTT was used to measure the inhibitory rates of HUVECs and the half inhibitory concentration (IC50).According to the experimental results,the HUVECs cultured in vitro were divided into control group(0.00 mmol/L Hcy),Hcy group(9.00 mmol/L Hcy)，and atorvastatin group(9.00 mmol/L Hcy＋１×10-3 mmol/L atorvastatin).After treated for 48 h,flow cytometry was used to detect the apoptotic rate of cells,the mRNA expression of Bcl-2 was analyzed by fluorescence quantitative PCR,the protein expression of Bcl-2 was detected by Western blotting method,and the methylation level of Bcl-2 promoter region was determined by nest touch-down PCR combined with methylation specific PCR(MSP).Results Compared with control group,the apoptotic rate of HUVECs in Hcy group was increased(P<0.01),the mRNA and protein expression levels of Bcl-2 were significantly decreased(P<0.01),and the Bcl-2 promoter region methylation level was also decreased(P<0.01).Compared with Hcy group,the apoptotic rate of HUVECs in atorvastatin group was decreased(P<0.01),the mRNA and protein expression levels of Bcl-2 gene were increased(P<0.05),and the Bcl-2 promoter region methylation level was also increased（P<0.05).Conclusion Atorvastatin can prevent the apoptosis of HUVECs induced by Hcy through regulating Bcl-2 methylation.

Key words: atorvastatin, atherosclerosis, homocysteine, Bcl-2 protein, DNA methylation, apoptosis